Square Cast Iron Finned Tube for Boiler Economizer
Square Cast Iron Finned Tube is a device used to enhance heat transfer. Fins are added to the exterior of the tube to improve heat transfer efficiency. It is suitable for high-temperature, high-pressure, and corrosive environments. It is widely used in industrial boilers and power plant boilers.
Material Characteristics of Cast Iron Finned Tubes
Made of cast iron (gray cast iron or ductile iron), it offers stable thermal conductivity and strong corrosion resistance. It can withstand flue gas temperatures of 300-400°C and is not easily deformed in high-temperature environments.
Structure and Function of Cast Iron Finned Tubes
Fin Design: The surface features a spiral or ribbed structure, significantly increasing the heating area within a limited space. This improves heat transfer efficiency by over 40% compared to conventional bare tubes.
Application Scenario: Primarily used in energy-saving economizer systems, this system recovers flue gas waste heat to preheat water or air, reducing fuel consumption and improving boiler thermal efficiency by 5%-8%.
Maintenance Characteristics of Cast Iron Finned Tubes
The surface is resistant to dust accumulation, and even small amounts of dirt can be removed with high-pressure water washing. The heat transfer efficiency degradation rate is less than 10% after long-term use, resulting in low maintenance costs.
Cast iron finned tubes are heat transfer components that combine cast iron with a fin structure. Their core characteristics and industrial applications can be summarized as follows:
1. Material Characteristics and Structural Design
Composition and Performance
Cast iron has a high carbon content (2.11%-4%) and contains free graphite (flake or spherical) in its structure, resulting in high brittleness and low tensile strength. However, it possesses excellent wear resistance and vibration damping capabilities. These characteristics make it suitable for heat transfer applications requiring resistance to wear or vibration, such as industrial boiler economizers.
Fin Structure Optimization
Cast iron finned tubes improve heat transfer efficiency by increasing fin surface area (e.g., through spiral winding or casting). Fin pitch is typically 2.5-8mm and can be adjusted based on cleaning requirements or heat transfer efficiency. Some products feature streamlined designs (such as 180-degree elbows) to accommodate complex piping layouts.
II. Industrial Applications
Boilers and Waste Heat Recovery
Cast iron finned tubes are widely used in industrial boiler economizers. They are compatible with economizer systems measuring 1500-2000mm and have a pressure resistance of 1.0-3.0 MPa. Their wear resistance is particularly suitable for waste heat recovery from flue gas containing particulate matter.
Heating Equipment
In residential heating applications, cast iron finned tubes can be enhanced with surface treatments (such as galvanizing) for corrosion resistance, making them suitable for use in humid or dusty environments. For example, in the renovation of older residential communities, compact cast iron finned tube radiators can address space constraints, with a single unit providing a heat output of up to 1600W.
Comparison with Other Finned Tube Materials
Compared to carbon steel finned tubes: Cast iron offers lower cost and greater wear resistance, but also offers lower thermal conductivity (carbon steel has a thermal conductivity of 45-50 W/(m·K)).